Measure the capacitance-vohage characteristic of LED by use the forward alternating ：current （ac） small signal method. Negative capacitance can be observed. Firstly put forward that negative capacitance phenomenon, which can be measured is surface phenomenon, and there are no negative capacitance. Firstly put forward that the capacitance of P-N junction in LED is equivalent to the variable capacitance when the forward voltage in particularly scope, the variable capacitance of the particular parameter make the phase current ...
